Snubbed truck



c. E. TACK 2,597,909

SNUBBED TRUCK.

4 Sheets-Sheet l chf Z. @che May 27, 1952 Filed Sept. 27, 1947 M ay 27,1952 C, E, TACK 2,597,909

SNUBBED TRUCK Filed Sept. 27. 1947 4 Sheets-Sheet 2 INVENTOR. Cafz/ c//C. E. TACK SNUBBBD TRUCK May 27, 1952 4 Sheets-Sheet 3 Filed Sept. 27,1947 INVENTOR. CZZJJZ E Zc C. E. TACK SNUBBED vTRUCK May 27, 1952 4sheets-sheet 4 Filed Sept. 27, 1947 JNVENTOR. Ccz'zZZ ZZzc// BY vPatented May 27, 1952 SNUBBED TRUCK Carl Tack,r Chicago,Ill.,-.=ass.ignor to American Steel Foundries;- Chicago,` I1l.,f-.acorporation: of

New Jersey Applicatiomseptember 27',y 1947,-'SeriallNo. 776,603

11 @lai-ms. l

This :invention relates to railway .cartrucks and :more particularly'toa friction devicejor damping oscillations of the truck' bolster .whichsupports the car body.

In .the prior art various trucks 'havejceenx proposed and a number have.been .placed inservice wherein bolster. oscillations .are dampedbyfrictiondevices associated with the bolsterfor `developing frictiontoresist its oscillations. .Such

arrangements have been generally .successfulineliminatingharmonic;action of the .bolster-:supporting springs andtheresultant harmfulV effect Well known to those skilled in the art.However, one fault inherent in all such devices vheretofore proposed inthe transmission `of vibrations,v from the truck frame to the bolsterand the .structure supported thereby, due to the fact that :the staticfriction developed in devices such as those `heretofore used for dampingpurposes f is relatively great in order to afford satisfactory:` kineticfriction to prevent harmonic oscillationsaof vthe bolster-supportingsprings.

'In other words, in prior art arrangements, whether the frictiondevicehas been mountedzon the frame for cooperation with thebolster .orhas been mounted on the bolster for cooperation with the frame, severevibrations have been transmitted from the frame to the bolster duringperiods when the bolster has vbeen static relative to the frame. Thisphenomena-has .beendue to the relatively great coeicient of static,friction inherent in such arrangements to afford `satisfactory kineticcoeiicient of friction. Reduction of thestatic coeicient of friction hasheretofore been regarded as impossible due to the ccnsequent reductionof the kinetic coeicient toa h useless` value.

Accordingly, a primary object of the :present invention is to afford afriction device for damping oscillations of a railway car truckbolsterat av lower static coeicient of friction -than-has heretoforebeen possible.

Another object ofthe invention is to aforda friction device, such asabove-described, having a static coeicient of friction not substantiallygreaterthan the kinetic coeilicient to afford satisfactory damping ofbolster oscillations tat all times.

Still another object ofthe invention-is toireduce transmission ofvibrations fromithe frame tothe bolster by affordingmeans-for absorbingsuch vibrations and also capable of Adeveloping a'suicient kineticcoefficient of friction'tozaiford satisfactory damping vof bolsteroscillations.

Still another object of the inventionzisrto providexaifriction device,rsuch' as above-described, wherein Jthe static and Vkinetic: coecients Yof frictionn'are substantially equalto accommodate dampingiofzthebolsterloscillations-ata uniform coeiicient of )friction throughout thebolster stroke.

.flhepforegoingand Vother objects and advantages. of the inventionWillbecomeapparentfrom aiconsideration; of the following specificationand the accompanying draWingsw-herein:

:Figure 1 is afragmentary sideelevation of: a .car '..truck embodying.the invention;

:,'Illigure 2..is;.a sectionalview on the line .2-2

yof'fliigiure .1 :With the-bolster shown iny sidejv elevation;

'.FigurerS' isL a fragmentaryutop plan viewof the bolster 2 and,-iassociated friction devices with the side: framegshowninfsectionthrough the columns thereof;

Figure 4 is a sectional View on the line 4 4 of Figure. 3;

Figure 5 is a sectional viewon the line 5 5 l Vof-ligure 3;

.l Figure 6 is a fragmentary side elevational View .1 lFigurev'lisafsectionalview ofthe line '1 -lof `Figure 6 with the bolster showninside elevation;

Figure is-a fragmentary top plan view of the Abolster'shown-in Figures 6and 7 With the side framev shownin .section through the columnsthereof;y

`Figuresi9 .to 14, inc1usive,lllustrate the'novel friction.shoe.-utilized'in theY arrangement of Figures 6,150.58, Figure .9 beinga front elevational viewofthe shoe, -FigurelO being a side elevationalviewthereoffFigure. lllbeing a rear elevational view, kFigure .12 .beinga "fragmentary'top plan =view,v Figure l13 being a. fragmentarylbottomplanvieW, ,f and Figure 14 v:being .a fragmentary lsectionalviewonthelline i3d-'|14 of,- Figure 10;

.Figures "15 to 18 illustrate a modification. of .the :shoe .utilizedin` thearrangement :of .'.Figures y6 :to8,-.Figure.1f5'being= aside;elevational viewo'f thefshoer Figureslbeing a rear elevational view,Figure `1'7 ibeing A.a :fragmentary v top -plan view, .and-Figure lbeinga fragmentary `.bottomc plan view;-and

Figure'il l is aside-:elevational view of another modification of-rthef.shoe Y utilizedl in the :arrangement` offFigures 6y to 8.

One embodiment. of .my novel -truck arrangement is, shown iniFigures -I-toa 5 inclusive, ywhereinnthe'` side :Hamai-generally: designated f2,com- :prises tension '.and` .compression i members F4=and-f6 mergingadjacent corresponding ends thereof with columns 8 dening therewith thebolster opening l wtih widened upper portion I2 (Figure 1). The tensionmember beneath the bolster opening is a box section with the inboard andoutboard Webs l and |6 and the top and bottom chords |8 and 20 as wellas the vertical reinforcing rib 22 disposed intermediate the walls I4and |6. The top chord I8 is widened and formed with upstanding inboardand outboard flanges 24 and 26 defining a spring seat 28 upon which areseated a plurality of coil springs 30 aording support for the bolster,generally designated 32.

The bolster comprises the top and bottom walls 34 and 36 and the spacedside walls 38, and a pocket 40 is formed in each side of the bolster,

said pocket being defined in part by the inboard and outboard walls 42and 44 offset respectively at 46 and 48 and merging with a rear wall 50at the inner end of the pocket. Integrally formed with the inboard andoutboard walls 42 and 44 are the spaced ledges 52 and 54, said ledgespresenting wedge surfaces sloping upwardly and' outwardly toward theadjacent column and engaged at 56 and 58 respectively with wing portions60 and 62 of a friction shoe, generally designated 64, said shoecomprising a top wall 66 affording a seat 68 for the upper end of aspring l0, the lower end of said spring being seated at 'l2 against thebottom wall 36 of the bolster.

Each friction shoe 64 also comprises a front wall 14 for engagement at16 with a wear plate 18 mounted on the adjacent column 8. The wear plateis preferably one which has substantially the same static coefficient offriction as the kinetic coecient. Such a material having the followingcomposition may be obtained by conventional curing at about 325 F. andunder adequate pressure to produce the desired density:

. Parts by Material Weight Rubber 4. Phenolic Formaldehyde Resin 5.0Cashew Nut Shell Polymer. 3. 0 Graphite 7. 0 Bakelite impregnatedAsbestos W Y 70.0 Carbon Black 2.0 Barium Sulphate. 7. 5 White Lead 7. 5

Another such material is disclosed in United States Letters Patent No.2,052,779, issued'September 1, 1936, to Harvey J. Lidkea and Ray E.Spokes. It will be understood that any desired friction material may beutilized wherein the static coeflicient of friction is not appreoiablygreater than the kinetic coecient and preferably where they aresubstantially equal.

Each shoe also comprises a rear wall 80 offset at 82 to form ahandlelike loop received `within a complementary offset 84 in the rearAWall 50 of the pocket 40, the loop 82 being aligned with openings 86 inthe inboard and outboard walls 42 and 44. It will be understood that atool may be inserted into the openings 86 and may be engaged with theoifset portion 82 of the wall 80 whereby the shoe may be Withdrawn fromengagement with the associated wear plate 18 during assembly anddisassembly of the bolster and side frame.

As may be seen in Figures l and 5, the surfaces on the shoes are crownedfrom top tobottom thereof. It may also be noted that the bolster 32comprises inboard and outboard guidelugs 88 and 90 at each side thereoffor engagement with the inboard and outboard surfaces of the adjacentF., li)

column 8, the outboard lugs 90, as may be clearly seen in Figure l,being of less depth than the widened portion |2 of the bolster opening,whereby the bolster may be elevated therein and removed therefrom duringa quick wheel change Without disturbing the supporting springs 3D.

Figures 6 to 8 show another embodiment of the invention wherein theconstant coefficient friction material is carried by the shoe. In thisembodiment the truck is generally similar to that shown in Figures 1 to5 and comprises a side frame, generally designated |02, and a bolster|04 supported therefrom by springs |06 adjacent a column |08 integrallyformed with the frame adjacent each end thereof to define a bolsteropening H0 (Figure 6).

The bolster, as in the previously described embodiment, is a box-sectionmember with a pocket I I2 in each side thereof containing spaced wedgesurfaces H4 sloping downwardly from the adjacent column and engagingcomplementary wedge surfaces of a friction shoe, generally designatedH6, actuated by a spring ||8 seated on the bottom wall of the bolster.

The friction shoe I I6 is shown in detail in Figures 9-14 wherein itwill be seen that the shoe comprises a front wall |20 with a narrow up-Wardly extending projection |22 merging with a top wall |24 affording aseat on its under side for the before-mentioned spring ||8. The rear endof the top wall |24 is integrally formed with a diagonal rear Wall |26having at its lower extremity an inturned portion |28 (Figure 10)defining a loop or socket |30 to afford convenient means for keying theshoe within the bolster, as described in connection with the embodimentof Figures 1 to 5.

At each side thereof the shoe ||5 is formed with a diagonal wall orledge |32 connected at its upper end to the front wall |20 and to agusset |34 (Figure 10) formed with the top wall |24. The ledges |32, aswill be understood by a ccnsideration of Figures 6 and 8, are engageablewith the complementary wedge surfaces ||4 of the bolster. Each diagonalwall |32 is connected at its lower end to the inturned portion |28 ofthe rear wall |26 which is formed with a gusset |36 at each side thereofreinforcing its connection to the ledge |32. Each ledge |32 is connectedto the front wall |20 by a side wall |38 reinforced by a gusset |20.

A friction liner |42 is secured to the front surface of the wall |28 andis provided with spaced lugs |44 received within complementary openingsin Athe wall. The liner |42 is preferably formed of a constantcoeflicient friction material, such as that described in connection withFigures 1 to 5, and is bonded to the wall |20 by any desired thermalsetting cement.

Referring again to Figures 6 to 8, it may be noted that theabove-described construction of the friction shoe is such that theshoe-actuating spring ||8 is seated against the spring seat wall |24 ofthe shoe at a point above the top wall of the bolster |04, therebyaffording aV spring of maximum capacity. This feature'as above-noted, isaccommodated by the extension |22 of the front wall |20 of the shoe.

Referring now to Figures 15 to 1B,l a modified friction shoe, generallydesignated |50, is illustrated for use in connection with thearrangement of Figures 6 to 8. 'I'he shoe |50 comprises a front wall`|52 having an upwardly extending projection |54 integrally formed with atop YWall |56 affording a seat on its under side for the scribed. issecured to. the. front-Walle landcomprisesaneupwardlyiextendingprojection lilsoomf plernentaryato theproiection 154 .of e,.shee Theprojection All! is y'seouredby a bolt 5 H2 threaded.v .into'the-projection invalidi tbozznortion of. the; .top vWall- ISG joinedthereto. Beneath the v,bolts |12 .are a Apair ofA boltsf |14 thre dedthrough the-"frontwau |52 .andinto the. edges |64 adjacent the upperextremity thereof. fg-Beneathzthe bolts |14 vare :a naif of ab .ts H6threaded. through; the frontwall .lland nto the sidewalls 1.6.6. It-;may befnoted-.that-,by means ofthe above-,described arrangementtbe;.friction face. I 68.1s securelybolted'to theishoef ,|50 Joystud boltspassing through relatively thick sections ofthe shoe particularlydesigned@toaocommodate .this means of ,seouromont :Furthermore thefriction face |68 is ooextensivewithth ntre front wall |52 includingtheextension-E |54` thereof, thereby affording a somewhat greaterfriction area than in the previously described shoe IIE.

Figure 19 showsanother modification of a frictionshoe designed for usein .thearrangement of Figures 6 to 8. The modicationofligure 19 issubstantially identical with that shown in Figures 9 to 13 andcorresponding parts are identified by corresponding numerals. In Figure19.-each ledge. |32 is recessedy as at 200 to-receive a,.wedge faceorliner 202. of` constant coeicientfriction materiaLsuch. as .that abovedescribed,A thea liner 202having lugs or. bossest204 projecting` inP thecomplementary socket withinl .the ledge. 32gand being bondedtheretowithfany desiredther-mal settingfcement.

lt. may be noted. thatV the modification ofrEigure .19. isVsubstantially .identical with that of Figures 9 to 14 except for the.provisionvoffthe wedge face 202 having a static coecient of frictionnot greater than the kinetic coefficient of friction and preferablyabout equal thereto for the purpose of preventing sticking of the shoealong the associated bolster Wedge faces as sometimes occurs due to therelatively high static coeicient of friction at that point where thewedge face 202 is not utilized. It will also be understood that frictiondeveloped against the Wedge face 202 during oscillations of the lbolsterlaterally thereof between the side frame columns is substantiallyconstant.

It is to be understood that I do not Wish to be limited by the exactembodiments of the device shown which are merely by way of illustrationand not limitation as various and other forms of the device will, ofcourse, be apparent to those skilled in the art without departing fromthe spirit of the invention or the scope of the claims.

Iclaim:

1. A railway car truck comprising a side frame member with a column, abolster member springsupported adjacent said column, said bolster membercomprising top and bottom walls and spaced walls defining therewith abox section, a pocket in the bolster comprising a wedge surface slopingtoward said column, a friction shoe actuator in said pocket in wedgeengagement with said surface, said actuator comprising a spring ns.carried hereby, anothenmemberrsupported,by saidspringmeans. andsfriction-means f ondamping rela-.tira uertical vmcmement between.xsaidmembers-comprising@ friction: surface; fiXedwith respechtooneeoffthe members.;anotherffriction'surface carriedfby theothertmember. iandactuatingsmeansafor; urging saidiothersurfaceintorengagement .withthef-rstg mentionedsurfacef said-.actuatingmeansr-com- Drsingaspring.meanscarriedby one-of; ther-.meme ber-standoperatively. connected to said ,otherasurg. face.;l the-,surface .of.onenmember being; formada-.of material having ,asstatc f coefficient:of ffriction whcntengagedwith the-surface ofthe other meme ber:notsubstantiallygreater than .thek-inetic-.cof

efcientof'- friction offsaid materialwhen engaged withgthe'1- llast'-mentioned surface, and ;.said'fsur,. faceszibeingethe.sole means,v.undernormalrcontiiv. tions for 5 frctona'lly e resisting relativeYvertical moyementbetweensaid members.

33. A'rai'lway car truck comprisingfasidefiame.memberawithspacedcolumnsgai holsters-member springesupported between.said-columns, andrfric-f` tionfmeans.. at.: each ,side of said.ybolsterfmember A comprisinga pair, ofrffriction .surfaces -carriedebythebQISten-member .andi the .adjacentfcolumnfree spectively, wedge.meansyinterposed fbetweernone of said; surfacesAand,therelatedmembenfin .wedge engagement lwith; the .latter,. andspring s. means carriedy- -onezofr themembers `under. compressionagaingt saidvwedge means f for urgingffsaid-Qsuna faces. into ngagement,Yone of ,saidfsurfacesibeing formedy` gmaterial having .astaticcoefficient-mf friction-M henfengagedwith .the otherfsurfacegnot subsantiajllyg greater1 than the: kinetic, coefficient of, :-tion;;of;.sa id-;.materialv whenrengaged vwith saidotherrsurface.

4. A truck, according to claim 3, wherein the Wedge engagement of saidWedge means and the related member is along surfaces, one of which isformed of material having a static coefficient of friction when engagedwith the other surface not substantially greater than the kineticcoefficient of friction of said material when engaged with said othersurface.

5. A railway car truck .comprising a side frame with a column member, abolster member springsupported adjacent said column member, and frictionmeans comprising a wedge in wedge engagement with one of said membersalong corresponding wedge faces having a static coeiiicient of frictionnot substantially greater than their kinetic coefficient of friction,said wedge and the other member having engaged friction surfaces, one ofwhich is formed of material having a static coefcient of friction whenengaged with the other surface not substantially greater than thekinetic coefficient of friction of said material when engaged with saidother surface, and spring means carried by one of said members foractuating the wedge.

6. A railway car truck comprising a frame member, a bolster memberspring-supported therefrom,and friction means for damping relativevertical movement between said members comprising a friction surfacefixed with respect to one member, and a friction surface carried by theother member, one of said surfaces being formed of material having astatic'coeificient of friction when engaged with the other surface notgreater than the kinetic coefficient of said material when engaged withsaid other surface, said surfaces being the sole means under normalconditions for frictionally resisting relative vertical movement betweensaid members, and means for urging said surfaces into engagement.

7. A railway car truck comprising a side frame, a bolsterspring-supported thereby, a wedge face on the bolster sloping toward afriction surface on said frame, a friction shoe engaging said face andhaving a friction surface engaging said frame surface, and spring meanscarried by the bolster and engaged with said shoe for actuation thereof,one surface being formed of material having a kinetic coefficient offriction, when'e'ngaged with the other surface, at least equal to thestatic coefficient of friction of said material when engaged with saidother surface.. A 8. A railway car truck comprising a side frame memberwith a friction surface, a bolster member spring-supported by said sideframe member, a wedge face on said bolster member sloping toward saidfriction surface, a friction shoe engaging said face and having afriction surface engaging said frame surface, and spring meanscompressed between one of said members and said shoe for actuation ofthe latter, one of said surfaces being formed of material having akinetic coefficient of friction, when engaged with the other surface,not substantially less than the static coefficient of friction of saidmaterial when engaged with said other surface. 9. A railway car truckcomprising a sideframe member, a bolster member spring-supported by saidframe member, a friction shoe, said frame member and shoe having a pairof engageable friction surfaces, respectively, and said bolster memberand shoe having a pair of engageable wedge surfaces, respectively,slopin-g toward the friction surfaces and means carried by one of saidmembers for urging said shoe surfaces against the bolster member andside frame membersurfaces respectively, one surface of at least one pairbeing formed of material having a static coefficient of friction, whenengaged with the other surface of said one pair, not substantiallygreater than the kinetic coefficient of friction of said material whenengaged with said other surface of said one pair.

10; A railway car truck comprising a side frame member with a frictionsurface, a bolster member spring-supported by said frame member, afriction shoe carried by said bolster member, and means for urging saidshoe against said surface, said shoe and surface having engaged areas,one of which is formed of material having a static coefficient offriction, when engaged with the other area, not substantially greaterthan the kinetic coefficient of friction when engaged with said otherarea.

11. A railway car truck comprising a pair of relatively movable framemembers, and friction means for damping relative movement therebetweencomprising friction surfaces carried by respective members, one of saidsurfaces being formed of material having a static coefficient offriction not substantially in excess of its kinetic coefficient whenengaged with the other surface, and means for urging said surfaces intoengagement with each other.

CARL E. TACK.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,817,570 Latimer Aug. 4, 19312,052,779 Lidkea et al Sept. 1, 1936 2,147,398 Blunt Feb. 14, 19392,237,953' Webb Apr. 8, 1941 2,308,966 Saurer Jan. 19, 1943 2,348,942Watson M ay 16, 1944 2,378,414 Light June 19, 1945 2,381,378 Brown Aug.7, 1945 2,447,368 Schlegel et al Aug. 17, 1948 2,516,072 Piron July 18,1950

